2. Installation
8820-A2-GN20-30
March 2001
2-11
Connecting Power
The GranDSLAM chassis is furnished with two internally mounted, 35-amp circuit
breakers for redundant power (PWR A and PWR B). Two separate, unswitched,
individually fused power sources, each capable of safely handling this load, are
required for power redundancy.
The chassis provides either front or rear power access connections. Rear power
access is recommended due to ease of installation. Selecting the rear power
access method also eliminates the need for routing large 8-gauge wires to the
PEMs on the front of the chassis. The PEMs contain the 35-amp circuit breakers,
isolation, and other power conditioning-type circuitry and are always required for
operation, even if rear power access wiring is installed.
WARNING:
!
While power connections can be made to either the front or the rear of
the chassis, they must not be made to both at the same time.
Front Power Access
Front power access is made via two PEMs which are located in the front, lower left
side of the chassis. PEM A is located on the left, while PEM B is on the right.
NOTE:
Both PEMs must be powered, or else the MCP alarm will activate.
The 48 VDC power wiring requires the use of #8 AWG stranded wires. Use the
following procedure to connect power to the front.
SERIAL
SMCM
CLOCK
A
ALARM
2
4
6
8
10
12
14
16
18
1
3
5
7
9
11
13
15
17
LAN/WAN SLOT
B
CLOCK
B
A
SERIAL
MCC
AC
ALARM
48V R
T
N
48V NEG
POWER ENTRY MODULE
LEFT UNIT: LINE A
RIGHT UNIT: LINE B
WARNING! POWER MUST BE DISCONNECTED A
T THE SOURCE
BEFORE REMOVING OR INSTALLING THIS PWR ENTR
Y MODULE
48V R
T
N
48V NEG
POWER ENTRY MODULE
LEFT UNIT: LINE A
RIGHT UNIT: LINE B
WARNING! POWER MUST BE DISCONNECTED A
T THE SOURCE
BEFORE REMOVING OR INSTALLING THIS PWR ENTR
Y MODULE
00-15326a-02
PEM
Circuit
Breaker
48V R
T
N
48V NEG
POWER ENTRY MODULE
LEFT UNIT: LINE A
RIGHT UNIT: LINE B
WARNING!
POWER MUST BE DISCONNECTED AT THE SOURCE
BEFORE REMOVING OR INSTALLING THIS PWR ENTRY MODULE
O
PEM
A
PEM
B
